Distilling apparatus and method



June 3, 1924.

P. H. TODD DISTILLING APPARATUS AND METHOD INVENTOR. Paul HxTodd gW W ATTORNEY.$

Patented June 3, 1924- UNITED STATES PATENTTOFFVICE';

PAUL 'ronn, or KALAMAZOO, MICHIGAN, ASSIGNOR ro ao nn co rANY, or .Q

KALAMAZOO, MICHIGAN.

nIsrrLmNG APPARATUS AND METHOD.

Application filedMarch'l i, 1922. Serial No. 543,568.

To all whom it may concern Be it known that I, PAUL H. TODD, a citizen of the United States, residing at the city and county of Kalamazoo, State of Michigan, have invented certain new and useful Improvements in Distilling Apparatus and Methods, of which the following is a specification.

This invention relates to improvements in distilling apparatus and method.

In the steam distillation of essential and volatile oils from plants and other substances in which they occur, suchas peppermint and Spearmint, the oil vapor and steam pass into the condenser together and on being condensed flow into a receptacle. The oil separating from the water distillate is removed therefrom. There is, however, a certain amount of the essential oils held in solu: tion, approximately one-tenth of one per cent in the cases of peppermint and spear-mint. This has, as far'as applicant is aware, been heretofore a loss, as no practical means of V recovering it has been discovered or p'rac-' tised, r

It is the main objects of applicants invention- First, to provide an improved method of recovering the dissolved, essential oils from this distillate water.

Second, to provide an improved apparatus for recovering oils held in solution in the water distillate residue of steam distillation.

Further objects, and objects relating to structural details, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification. The invention is clearly defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is clearly illustrated in the accompanying drawings,,forming a part of this application, in which:

The figure is an elevation of an apparatus embodying the features of my invention, various parts being shown conventionally.

I will first describe my improved method of recovering essential oils from the'water distillate of essential oil distillation and then the apparatus by which it may besuccessfully practised.

After the oil has been separated from the distillate the distillate water residue is redistilled by passing steam therethrough until due of steam or water distillation of pepper-' mint and spearmint amounts roughly to onetenth of one per cent'and that if this be redistilled and the resulting vapor condensed, practically all of the oil in solution will be carried over with the steam in a concentration about ten times greater than that of the water distillate treated. f For instance, if one thousand pounds ofthe" water distillate containing approximately one'pound of oil is redistilled by this method, the one pound of oil will practically all come over with the first one hundredpounds of steam, so that if the redistillation is stopped at this point one per cent of the redistillate will be oil and at this concentration only onetenth of the oil will beheld in solution and the balance will rise to the top of the separator and can be drawn off. v

The water of this redistillation can be drawn off, and be redistilled again in the manner stated.

The apparatus shown in the accompanying drawing consists of a storage tank 1 having a supplyJpipe 2. I provide a pair of stills 3 and a condenser l of the tubular type, that is, there are a series of tubes disposed within a cooling medium chamber. The stills are both connected at their upper ends by the pipes?) to the condenser pipes or flues. These connections 5 are independently controlled by the valves 6 so that either may be out o and the other opened. The cooling medium chamber of the condenser is connected by the pipes 7 to both stills, these ipes being controlled by the valves 8 so t at the cooling medium chamber may be connected to deliver to either still.

The stills are provided with steam pipes indicated at 9 and controlled by the valves 10, the steam pipes being disposed at the bottom of thestills so that the steam bubbles up through the liquid within the stills and the vapor is carried over through the pipes 5 to the condenser.

The condenser is connected to the separator 11 by the pipe 12, the condenser being provided with a draw-oil pipe 13 and with a water distillate discharge pipe 14: delivering to the reservoir 15. The intake 16 of the pump 17 is connected by the pipe 18 to this reservoir and by the pipe 19 to the storage reservoir 1. The pump discharge is connected by the pipe 20 to the cooling medium chamber of the condenser. These parts are shown mainly in conventional form as the structural details thereof form no part of my present invention.

The utilizing of the water distillate to be redistilled as a cooling medium for the condenser pie-heats such water thereby securing a considerable saving. In practice one still is in operation at a time the other being filled by means of the pump through the condensing chamber the valves 6 and 8 being suitably manipulated.

A large amount of the distillation water may be rapidly handled with this apparatus and a very high percent-age of the essential oil contentthereof is recovered. The water residue of each charge or batch is drawn off through the discharge faucets 21.

It is believed that the disclosure made will enable those skilled in the art to which my invention relates to practice the same in an eflicient manner and I have not therefore attempted to illustrate or describe certain modifications and adaptations which may be desirable for particular installations.

Having thus described my invention, what I'claim as new and desire to secure by Letters Patent, is:

1. The method of recovering essential oils held in solution in distillate water residue of distillation consisting of re-distilling such distillate water residue until approximately one-tenth of such distillate water residue has been re-distilled, condensing and ate residue until such fraction of such dis tillate Water residue as will carry over the bulk of the oils has been discharged, condensing and removing the oil from the redistillate, and adding the water residue of such distillate to another charge of distillate water for redistilling.

4:. A' distilling apparatus comprising a pair of stills a condenser having a cooling medium chamber, independent valved discharge connections from said stills to said condenser independent valved discharge connections from the cooling medium chamber of said condenser to said stills wherebythe medium to be distilled may be passed through said condenser as a cooling medium therefor and discharged to either of said stills, a separator to which said condenser dis charges, a discharge reservoir for said separator, a storage reservoir, a pump having its discharge connected to the cooling medium chamber of said condenser and inlet connections 'to said storage and separator reservoirs, and heating means for said stills.

In witness whereof, I have hereunto set my hand and seal.

PAUL H. TODD. Ls 

